Dental



(No Model.) v

' H. S. LOWRY.

I DENTAL APPLIANCE. No. 576,593. Patented Feb. 9, 1897.

liy

NITE STATES PATENT Fries.

IIOIVARD S. LO\VRY, OF KANSAS CITY, MISSOURI.

DENTAL APPLIANCE.

SPECIFICATION forming part of Letters Patent No. 576,593, dated February9, 1897.

Application filed March 28, 1896. Serial No. 585,284. (No model.)

T0 at whom it may concern.-

Be it known that I, HOWARD S. LOWRY, of Kansas City, Jackson county,Missouri, have invented certain new and useful Improvements in DentalAppliances, of which the following is a full, clear, and exactdescription, reference being had to the accompanying drawings, forming apart thereof.

My invention relates to dental appliances, and more particularly to thatclass of dental appliances for forming or contouring metallic orartificial tooth-crowns or side contours.

Previous to my invention various methods and appliances have beenemployed for these purposes, the most successful among which are themethod of and appliance for molding soft-metal dies having the surfaceto be reproduced artificially intaglio, by burnishing the metallic plateto form the crown or side contour therein; but this method, Whilesuperior to any other which has been followed in practice, has onerather serious objection in that in molding said dies the metal used,which fuses at a low temperature, does not follow or penetrate closelythe sharply-defined fissures and outlines of the mold from which saiddie receives its intaglio impression, and consequently when the metallicplate of gold or other metal is burnished or swaged into the die toproduce the crown or side contour, as the case may be, it is notprovided with the fissures and sharply-defined outline of the tooth ormodel from which the die was produced, and therefore but imperfectlyarticulates with the opposing tooth above.

My method and the appliances which I use in its execution obviate thisdisadvantage, and an artificial crown or side contour is produced inwhich the fissures or outlines are an exact counterpart orreprod notionof the original tooth, pattern, or model by which the die is cast.

WVith the object in view then of producing artificial tooth-crowns whichare farmore perfect in their likeness to the originals or models thanany heretofore produced, and also with the object of producing suchartificial crowns or contours more expeditiously, conveniently, andcheaply, the invention consists incertain novel and peculiar features ofconstruction and combination of parts which will be hereinafterdescribed and claimed.

In order that the invention may be fully understood, I will proceed todescribe it with reference to the accompanying drawings, in which-Figure 1 represents, partly in side elevation for producing artificialtooth-crowns or contours. Fig. 2 represents in vertical section a viewshowing the mating dies and the toothcrown contoured and interposedbetween them. Fig. 3 is a detail perspective view of one of thedie-selecting caps. Fig. 4 represents in perspective a pair of pliersfor holding the crown-cap in position relative to the band of the crownuntil it is reliably secured in such position.

Referring to said drawings in detail, 1 designates a substantial metalbase provided with a cavity 2, preferablyrectangular, in its upper side.Extending upwardly from said base is an arm 3, which terminates at itsupper end in a vertical guide-sleeve 4, which is arranged verticallyabove or overhangs the cavity 2. Said sleeve is provided with a radialpassage 5, and fitting loosely but snugly therein is a pin 6. A spring 7is located in said sleeve and bears at its inner end against the pin 6and at its outer end against a screwplug 8,which is screwed in the outerend of said passage. By this arrangement it is obvious that said spring7, which is of the expansive type, holds the pin 6, advanced with ayielding pressure, into frictional engagement with the plunger 9,extending vertically and adapted to reciprocate through the guide-sleeve4. By

and partly in vertical section, an appliance this construction it isobvious also that the pressure of the pin against said plunger may beincreased or diminished at will by simply screwing said plug 8 fartherin or out. This object may be accomplished also by removing said plugand said spring, stretching the lat ter longitudinally, and thenreplacing it in position and replacing the plug also. Thisspring-pressure is only sufficient and the spring-actuated pin is onlydesigned to support the plunger at any desired point of adjustment.

10 designates a plate of lead or equivalent material which is located inthe recess or lCO cavity :2, and 11 an extremely-hard-metalintaglio-impression die. This die is an accurate reproduction of theoriginal core or model around which it was cast, owing to the fact thatit is composed of a composition metal which fuses at. a high temperatureand becomes so liquid that it follows and flows into every fissure orcrevice of the model or core, in order that the outline shall be sharplyand clearly defined. These dies cannot be produced by molding, but mustbe cast in sand in the customary manner. It is fully as hard as steel,and it is much superior to the latter in thatits wearing qualities aresuperior, and hence crowns or contours may be manufactured from thesedies by swaging without any appreciable wear upon the same. Thisadvantage will be appreciated by the profession, as with dies made ashereinbefore indicated after each crown is swaged thereon the die isunfit for further service and must be fused and molded again if it bedesirable to produce a second crown or contour. This molding process isobjectionable, too, owing to the fact that the operation sometimes hasto be repeated a number of times before an accurate die, 1'. 6., onewithout a flaw, can be produced. This die is placed upon the leadplateseat 10 in the recess 2, within which it fits snugly, and a plate ofgold or other metal 13 is placed upon it, so as to bridge the intaglioimpression 12 of the die, and upon said plate is placed a leaden orothercompressible ball 11. To produce an artificial crown now, all thatis necessary is to strike the upper end of the plunger a sharp blow witha mallet, which causes it in descending to compress the leaden ball andthereby the interposed plate 13 into the intaglio impression or cavity12, and also by the force of said descent to set the die firmly andsquarely upon the lead plate 10, which prevents any possible reboundingor bouncing tendency of the die, which it would have if it were placeddirectly upon the hard cast-metal base 1. Thus it will be seen that withone blow of the mallet a mating die for the die 11 is formed and forcedinto position simultaneously, so that the interposed plate mustabsolutely follow the outlines and crevices or cavities of the surfaceor contour to be reproduced, and it is also obvious that when thusformed and driven home said mating die cannot rebound or springupwardly, owing to the fact that the spring-actuated pin 6 prevents theslightest upward movement of the plunger. hen the parts are thusarranged, which is accomplished in an instant, one or two additionalsharp blows with the mallet upon the plunger are sufficient to completethe formation of the artificial crown or side contour, as the case maybe, which crown or contour is an exact duplicate in all its lines of themodel or core upon which the die 11 is cast. The plunger is thenelevated, the die removed, and the mating die ll and the artificialcrown 13 rem oved.

customary manner to fit snugly upon the band, and it is secured in suchposition in the customary manner.

In practice there will be about one hundred and forty-four, more orless, of these dies 11, all of them in clearness of outlinecorresponding to the natural tooth, and each of them provided with asmall counterpart cap designated by the numeral 12*, (illustrated inFig. 3,} which the dentist will use as the means for quickly selectingthe die to be employed in connection with the band of the tooth to becrowned, that is, when it is desired to select a particular crown for aband of a certain contour one of these caps is picked up quickly andeasily by the dentistand is fitted upon said hand. If it does not fitaccurately, it is placed back in its proper position and anotherselected, and this operation is repeated until the cap of the requisiteformation and contour is obtained. The die corresponding to such cap istherefore the die from which. the crown must be made in the manneralready described.

It is obvious, of course, that it will be practically impossible to takethe dies and fit them to the contour of the bands, as a great deal oftime would be wasted by so doing.

Thus it will be seen that I have produced appliances for makingartificial crowns or side contours in a most expeditious and approvedmanner which are cheap of manufacture, simple and durable ofconstruction, and easily handled, and by which more perfect results areattained than has been possible heretofore.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a dental appliance, the combination of a base or anvil a femaledie thereon, a vertical reciprocatory plunger arranged over thedie-cavity, and a ball of lead arranged vertically below the plunger,uninclosed by walls and resting loosely upon the plate to be swagcd, andvertically over the cavity of the die, for the purpose set forth.

2. A dental appliance, comprising a metallic base provided with a recessin its upper side, an arm projecting upwardly from said base andprovided with a vertical guide-sleeve which overhangs said recess,aplunger in said sleeve, a lead plate in said recess, anint-aglioimpression die within said recess and seated upon said leadplate, and upon which die the crown-forming plate is placed, a compressrble ball upon said crown-forming plate, and a spring-actuated pin,bearing frictionally against the plunger, to hold it at any desiredpoint of adjustment, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

IIOXVARI) S. LOlVR-Y.

\Vitnesses II. E. PRICE, G. Y. Tnonru.

